Public network access to the API app service is enabled

[jonnyry]

Public network access is enabled to the API app service, even though it has a private endpoint which the app gateway uses (https://microsoft.github.io/AzureTRE/v0.16.0/assets/architecture-azure.png)

public_network_access_enabled is not defined here (and therefore defaults to true):

AzureTRE/core/terraform/api-webapp.tf

Line 20 in 1ffb09b

resource "azurerm_linux_web_app" "api" {